Lock with push-button operated bolt

ABSTRACT

A lock with a push-button forming a cylindrical plug with tumbler plates or pins and having a ramp retracting the bolt against the action of a spring, wherein the push-button plug is movable in rotation and translatory motion through direct contact with a stator formed with two plate or pin releasing grooves and directly secured to one of the two components (door or door frame) of the closing arrangement using the lock whereby the push-button plug is movable for two given rotary positions of the plug and of the removable key thereof.

United States Patent Lipschutz Nov. 18, 1975 LOCK WITH PUSH-BUTTONOPERATED BOLT Inventor: Paul Lipschutz, Croissy-sur-Seine,

France Assignee: Societe dExploitation des Brevets NEIMAN, Courbevoie,France Filed: Oct. 19, 1973 Appl. No; 408,209

Foreign Application Priority Data Octv 20, 1972 France 72.37254 Feb. 28,1973 France 73.07027 US. Cl. 70/81; 70/149; 70/360; 292/170 Int. (11.E05B 65/44 Field of Search 70/81, 85, 149, 360; 292/170, DIG. 38

References Cited UNITED STATES PATENTS Jacobi 70/81 FOREIGN PATENTS ORAPPLICATIONS 1,370,164 7/1964 France 70/81 Primary ExaminerAlbert G.Craig, Jr. Attorney, Agent, or Firm-Nolte and Nolte ABSIRACT A lock witha push-button forming a cylindrical plug with tumbler plates or pins andhaving a ramp retracting the bolt against the action of a spring,wherein the push-button plug is movable in rotation and translatorymotion through direct contact with a stator formed with two plate or pinreleasing grooves and directly secured to one of the two components(door or door frame) of the closing arrangement using the lock wherebythe pushbutton plug is movable for two given rotary positions of theplug and of the removable key thereof.

10 Claims, 13 Drawing Figures U.S.- Patent Nov. 18,1975 Sheet10f23,919,866

US. Patent Nov. 18,1975 Sheet20f2 3,919,866

LOQK WITH PUSH-BUTTON OPERATED BOLT The present invention relates tokey-operated and push-button responsive locks or safety locks used inbuildings, metallic furniture and automotive vehicles as well as in somecounting devices.

One of the objects of the invention is to reduce the cost price of sucha lock thereby to promote the commercial difiusion offered by itsvarious applications.

Another object of the invention is to simplify the design andmanufacture of this kind of lock, thereby to automatically achieve areduction in manufacturing tools or implements, in manufacturing time,in the stocks, storage and supplies of component parts as well as in theterms of deliveries.

A further object is to simplify the mounting or assembly of the lockproper and the mounting of the closing constructions to be operatedthereby.

Still another object of the invention is to increase the reliabilitywhich as everybody knows increases when the number of component partsdecreases.

A conventional lock of the same kind consists essentially of three mainelements:

l. a rotor or rotary member driven by the key and comprising extensibletumbler pins or plates for locking purposes the retraction of which,achieved through the wards or teeth of the key in accordance with a codewhich is peculiar thereto, provides for the absolute continuity of thecylindrical contact interface between said rotor and the member statedhereinafter, thereby enabling to rotate the key and rotor assembly;

2. a stator engaged by the tumbler plates or pins of the rotor toachieve the locking action and serving at the same time as apush-button;

3. a lock body adapted to be secured either to the stationary frame orto the movable panel or door to be closed, which body receives andaccommodates the stator and serves as a guide or slideway for the statorin its translatory motion.

The lock which is the subject matter of the present invention onlycomprises two elements instead of three, which elements are thefollowing:

l. the rotor acting as a push-button;

2. the stator which forms at the same time the body where the rotor issliding.

Thus an important component part has been dispensed with.

Yet this new lock accomplishes all the functions of a conventional lock.

Embodiments of the invention are illustrated in the accompanyingdrawings wherein:

FIG. 1 is a longitudinal section of a lock of this invention with thekey inserted;

FIG. 2 is a view in cross-section taken upon the line llII in FIG. 1;

FIG. 3 shows in longitudinal section the lock of FIG. 1 in unlockedcondition with the key removed;

FIG. 4 shown in longitudinal section the lock of FIG. 1 in lockedcondition and with the key removed;

FIG. 5 is a perspective view of the lock-bolt of the lock of FIG. 1;

FIG. 6 is a top view with a partial section taken upon the line VIVI inFIG. 4;

FIG. 7 is an end view of the push-button member shown in FIG. 6;

FIG. 8 shows in longitudinal section a second embodiment of theinvention;

FIG. 9 is a cross-section by the plane IX-IX in FIG.

FIG. 10 shows in longitudinal section the lock of FIG. 8 in the openposition;

FIG. 11 is a longitudinal section of the lock of FIG. 8 in the lockedcondition with the push-button pressed inwardly;

FIG. 12 is a longitudinal section of the lock of FIG. 4 in the lockedcondition and the push button in a rest position; and 7 FIG. 13 is aview in section taken upon the plane XIIIXIII in FIG. 12.

In FIG. 1 is shown the push-button l of generally cylindrical shapewhich holds tumbler plates and receives the key 2. It has therefore theability to rotate and to move into the stator 3 where it remains guided.Its end opposite from the button exhibits a prismatic extension 5 havinga ramp or like cam profile 4 which will cause the shifting motion of thelock-bolt; the portion 5 is not symmetrical with respect to the verticalaxial plane of FIGS. 1, 3, 4: as a matter of fact it has a shoulder 6'which will serve as an abutment or like stop for the ramp and for thebutton in the direction of inward motion (see FIG. 6) when the rotor islocked against angular rotation, the key having been removed (FIGS. 4and 6).

The body 3 is formed in its bottom end with a window or like opening 20one of the vertical sides of which is engaged in abutment by theshoulder 6 of the push-button 1 and its extension 5 (FIGS. 4 and 6).

The body 3 is extended by a cage 9 forming a transverse slideway for thelock-bolt 10.

Moreover this body is milled or cut out along a pair of symmetricalgrooves 7 and 7' which serve as a housing and guides for the tumblerplates 8 of the rotor 1 when the latter have moved out into the outwardextended position which is the case in FIG. 3, the key being withdrawn,after having turned the rotor through and the bolt having moved out intothe outward extended locked position (as examplified in FIG. 4).

The lock-bolt 10 which in the outward extended position engages a notchor like keeper, bolt-clasp or strikebox provided in the stationary partnot shown is driven into this locking position by a spring 12 whichbears on the one hand on a central protrusion 13 of said bolt and on theother hand in a cavity 14 of the body 3. The bolt 10 exhibits a nearlycentral appendix l5 projecting slightly from the end surface of the boltfor extending into a window or opening 11 of the cage 9: thus the upperportion of the appendix 15 under the action of the spring 12 comes inabutment against the upper inner face of the window 11 for limiting thevertical stroke (case illustrated in FIGS. 1, 2 and 4) of the bolt whenit moves out into locking position (FIGS. 1, 4 and 6).

The bolt 10 therefore exhibits at its centre towards the push-button theprotrusion 13 the shape of which is such as to comply with the followingrequirements: at the top or upper portion (FIGS. 1 and 3) it is designedto receive the thrust of the terminal ramp or cam portion 4 and at thebottom or downward located portion (FIGS. 4 and 6) there is a half-moonlike recess 16 cut out to avoid locking the rotor against rotation andto let the end of the ramp 4 move thereinto. The end portion inextension of said ramp has a semi-cylindrical shape (FIG. 2).

Owing to the suitable slant or pitch of the ramp 4 and to the shapesreferred to hereinabove, the thrust exerted upon the push-button 1applies a vertical component force on the spring 12 it compresses; in areverse manner the release of this spring 12 drives the pushbuttonoutwards.

The structure of the bolt is shown in perspective view in FIG. 5 where aportion of the upper end of this bolt has been assumed to be omitted orremoved to let show the appendix which serves as a stop abutment for thevertical motion of said bolt against the window 11 in the slideway-likecage 9 forming the end of the body.

To limit the stroke of the rotor 1 to the left in the Figures, ashoulder or collar 18 has been provided to abut against the innerportion or face of the cover 17 of the lock which on assembling iscrimped or seated onto the body 3 which carries teeth such as 19 forbeing securely positioned onto the stationary frame or the door orclosure panel of the closing construction to be fitted therewith.

Having been thus described the operation of the device is easilyunderstandable:

Assuming the lock locked in the position shown in FIG. 4, the key havingbeen removed, the push-button in the outward extended position, the ramp4 is down; in view of the presence of the shoulder 6, the push-buttoncannot be moved or driven inwards although the outward extended tumblerplates in the groove 7 may allow a motion to the right. It is thereforeimpossible to move back the bolt 10 downwards by acting against theforce of the spring 12.

If the suitable key is inserted into the lock, the tumbler plates areretracted and the rotor may be rotated through 180 to bring it into theposition shown in FIG. 1; the key may then be withdrawn and thepush-button may be depressed as shown in FIG. 3: as a matter of fact theshoulder 6 of the push-button does no longer meet the edge of the window20, the push-button having rotated through 180 and the tumbler plates 8in the position shown in the Figure may slide in the groove 7'. Duringthis allowed movement, the ramp 4 bears at first with its rounded endonto the gouge-shaped formation 21 which is complementary of theprotrusion 6 and then with its prismatic portion so that it brings backdownwards the bolt assembly 10 while compressing the spring 12.

The bolt being retracted, the lock and the closure arrangement operatedthereby are in the open position.

When releasing the push-button l the bolt moves up again into the lockedposition under the action of the spring 12 whereas the horizontalcomponent force drives said push-button outwards to project from thebody.

To prevent any motion of the bolt and push-button, it is necessary toinsert the key again and having retracted the tumbler plates to bringthe rotor through a rotation of 180 which is then possible into theposition shown in FIG. 4 as at the beginning of this explanation.

The previous embodiment directed to a new keyresponsive push-buttonoperated lock thus reduces from three to two the number of componentparts by eliminating an intermediate bushing or sleeve between thestator of the lock, adapted to be mounted onto the frame or closingpanel, and the rotor carrying the tumbler plates locking or holding sameagainst rotation.

Now as to the kind of closing appliance, new standards have been set forsafety reasons:

in the first place the substitution for all the sharp angles by roundswith a least radius of curvature of 2.5

mm and the omission of any projections likely to hurt the passengers incase of sudden stop;

in the second place the closure panel, shutter or door which generallyreceives or accomodates the push-button must not open spontaneouslyunder the influence of a deceleration of 30 g minimum. As a matter offact such an untimely or undue opening would place the,

shutter or panel opening at like a knife opposite to the body and forsome shutters or panels in front of the In FIG. 8 is shown thepush-button 1 provided with its 2 key 2 the insertion of which hascaused the retraction of the tumbler plates 8 thereby providing fullpossibility of rotating the barrel or plug and of depressing thepush-button against the reaction of the spring 22.

The body or stator 3 which guides the button 1 is hollowed out or milledalong a pair of symmetrical grooves 7, 7'. Through rotation of the key 2which is withdrawn afterwards the outward extension of the tumblerplates is achieved (see FIGS. 10 to 13).

The stator 3 is extended by an end cage 9 receiving the lockbolt l0 andformed with a window 20 and an opening 1 1 both of which are positionedin registering relationship with the centre line of the button 1. Thestator 3 is formed with guide walls for the lock bolt shown in FIG. 9.

The button 1 is extended by a cylindrical portion which merges endwiseinto a prismatic portion 5 cut into a bevel-shaped configuration 4' atits end, which bevelled shaped is adapted to bring the lock-bolt back toits unlocked or inoperative position.

This end 5 and its bevel are perfectly symmetrical with respect to thediametral plane extending in parallel relation to the section in FIG. 8.The push-button 1 is under the dependence of a helical spring 22 whichrests on the bottom of stator 3 and on the shoulder featured by thediscontinuity between that portion of the bottom which accommodates thetumbler plates and the cylindrical part.

The lock-bolt 10 has its upper end rounded to facilitate the closingoperation through a simple pressure exerted upon the door or shutter orlike closure panel. It moves into a bolt-clasp or like strike-box of thestationary frame not shown. For this purpose it is pushed by a helicalspring 12 centred on a small post 26 cast in one piece with its bearingportion 23, and has its other end disposed in a cavity 25 well shown inFIG. 9 and which is formed in a central protrusion 21 of the lock-bolt.

Towards the push-button, this protrusion 21 is ended at the top by achamfer at 45 adapted to receive the thrust of the bevelled portion 4 ofsaid button and at the bottom and in the reverse direction by a widebevelled portion 16, the use of which will be set forth later. Thecentring area 26 as well as the spring and cavity 25 have not theircentre line in registering relation to the vertical plane of symmetryX-X in FIG. 9 but are offset or shifted sidewards to lighten these partsand to make the manufacture and mounting or assembling easier.

Moreover the lock-bolt is provided with a tongue or the like the upperedge of which comes in abutment against the lower edge of the opening 11of the stator. This abutment or stop 15, the spring 12 and its bearingsare all located in the same vertical plane for imparting to theresilient reaction of the spring its full efficiency.

The body 1 carries at its rear end assembling holes such as 24 which maybe tapped to receive mounting screws extending through the parts of thestationary frame (or of the door as the case may be) to be fitted withthe lock.

The operation of the device thus described is easy to understand. Itwill be assumed that the door has been previously closed as shown inFIG. 8 and that it is desired to open same. To this end the push-button1 is depressed and compresses the spring 12 until the bevel 4' bearsupon the chamfer of the protrusion 21 of the lock-bolt 10 therebyforcing same downwards so that the lock-bolt is released or freed. Thekey may be dispensed with to reach this position shown in FIG. 10. Thenthe release of the push-button will release the lock-bolt. To carry outthe full locking operation however the key should be inserted again asshown in FIG. 8 thereby causing the tumbler plates to be retracted andthe barrel-shaped plug to rotate through 180. When removing the key andreleasing the push-button, FIG. 12 shows that the bevel 4' comes infront of and below the bevel 16 of the lock-bolt 10 the outward extendedposition of which leaves a void or empty space large enough for possiblyaccommodating the prismatic end 5'. Thus owing to this arrangement andas shown in FIG. 11, the push-button 1 may be fully depressed or driveninwards through accidental engagement by the body of a passenger of thevehicle without in so far the lock-bolt 10 being caused to ceaseremaining in its boltclasp and without in so far the shutter being ableto open. The first safety requirement set forth at the beginning of thespecification is thus complied with.

Referring again to the position shown in FIG. 8, the key should beinserted again thereby causing the tumbler plates to be retracted andenabling the barrel like plug and the push-button 1 to be rotatedthrough 180 when withdrawing the key the retraction of the lockbolt maybe effected and the button maybe pushed to come back to the positionillustrated by FIG. 10.

The removal of the sharp angles may be carried out through a simpledesign to comply always with the first requirement which is fully met ifthe driver withdraws the key.

As to the second requirement it is complied with by the combination oftwo arrangements and of the lightening of the weight of the partsachieved:

a. through omission of the conventional bushing or sleeve between thebarrel or rotor 1 and the body 3;

b. through lightening the weight of the lock-bolt 10 by making itshorter;

c. through thinning the prismatic end of the push-button 1;

(1. through a side fastening of the body 3; and by outer side recessesformed in the same body 3; and at last by the presence of the additionalspring 22 directly opposing or resisting the depression of the buttoninwards through simple inertia or through contact in the case of theunlocked shutter or like closur panel.

It should be understood that the present invention is not at all limitedto the forms of embodiments described and shown which have been given byway of example only. In particular it comprises all the meansconstituting technical equivalents of the means described as well astheir combinations if same are carried out according to the gist of theinvention and used or put into practice within the scope of the appendedclaims.

What is claimed is:

1. A key-responsive safety lock with a movable lockbolt biased by aspring to be mounted on a closure construction consisting of a movableclosure panel and a stationary frame, said lock comprising a push-buttonhaving a ramp operating the retraction of said bolt against the actionof said spring, said push-button forming a barrel-like cylindrical plugof the safety lock housed in a stator and accomodating tumbler means,said push-button being movable in rotation and translatory motionthrough direct contact with said stator, said stator being formed with apair of grooves for receiving said tumbler means, said stator beingdirectly secured to one of the two elements consisting of said closurepanel and said stationary frame, said push-button being movable inrotation between two angular r0- tary positions wherein said tumblerplates and said grooves being aligned with one another, said lock-boltcomprising a protrusion engageable with said ramp so that said springurging said lock-bolt back into its operative outward extending lockingposition serves at the same time the purpose through reaction of saidprotrusion on said ramp of moving said push-button back into its outwardprojecting position when this is allowed by the orientation of saidpush-button with respect to said grooves of said stator, wherein saidramp of said pushbutton is formed with a shoulder, whereas said statorhas an intermediate partition wall situated between those statorportions in which said push-button and said lock-bolt are disposed andformed with a window serving to guide said push-button, said shoulderand one edge of said window being in abutting relationship in the one ofsaid rotary positions of said push-button cor responding to thelock-bolt locking position thereof.

2. A lock according to claim 1 wherein said protrusion is situated inthe center of said lock-bolt and is provided with slant edges at anangle matching with that of said ramp of said push-button and adapted tocooperate therewith.

3. A key-responsive safety lock with a movable lockbolt biased by aspring to be mounted on a closure construction consisting of a movableclosure panel and a stationary frame, said lock comprising a push-buttonhaving a ramp operating the retraction of said bolt against the actionof said spring, said push-button forming a barrel-like cylindrical plugof the safety lock housed in a stator and accommodating tumbler means,said push-button being movable in rotation and translatory motionthrough direct contact with said stator, said stator being formed with apair of grooves for receiving said tumbler means, said stator beingdirectly secured to one of the two elements consisting of said closurepanel and said stationary frame, said push-button being movable inrotation between two angular rotary positions wherein said tumblerplates and said grooves being aligned with one another, said lock-boltcomprising a protrusion engageable with said ramp so that said springurging said lock-bolt back into its operative outward extending lockingposition serves at the 7 same time the purpose through reaction of saidprotrusion on said ramp of moving said push-button back into its outwardprojecting position when this is allowed by the orientation of saidpush-button with respect to said grooves of said stator, wherein saidlock-bolt comprises stop means formed by a laterally outwardlyprotrusion appendix and said stator comprises means constituted by awindow provided in the corresponding wall of said stator, said appendixand one edge of said window being in abutting relationship when saidlock-bolt is in its locking position.

4. A lock according to claim 3 wherein said lock-bolt with saidprotrusion and said stop means is made in one integral piece withcavities on either side of said protrusion.

5. A lock according to claim 4, wherein said spring is positioned belowsaid protrusion with its upper part in said cavity undeneath saidprotrusion.

6. A lock according to claim 5, wherein there is provided a secondhelical spring coaxial with said pushbutton and urging same back intooutward protruding position, the action of said second helical springbeing thereby added to the reaction of said biasing spring on saidlock-bolt.

7. A key-responsive safety lock with a movable lockbolt biased by aspring to be mounted on a closure construction consisting of a movableclosure panel and a stationary frame, said lock comprising a push-buttonhaving a ramp operating the retraction of said bolt against the actionof said spring, said push-button forming a barrel-like cylindrical plugof the safety lock housed in a stator and accommodating tumbler means,said push-button being movable in rotation and translatory motionthrough direct contact with the said stator, said stator being formedwith a pair of grooves for receiving said tumbler means, said statorbeing directly secured to one of the two elements consisting of said 8closure panel and said stationary frame, said push-button being movablein rotation between two angular rotary positions wherein said tumblerplates and said grooves being aligned with one another, said lock-boltcomprising a protrusion engageable with said ramp so that said springurging said lock-bolt back into its operative outward extending lockingposition serves at the same time the purpose through reaction of saidprotrusion of said ramp of moving said push-button back into its outwardprojecting position when this is allowed by the orientation of saidpush-button with respect to said grooves of said stator, a secondhelical spring coaxial with said push-button and urging same back intooutward protruding position being provided, wherein said lock-bolt isformed with a side nose, said lock-bolt biasing spring is offset withrespect to the center line of said lock-bolt and bearing upon said sidenose, a portion of said lock-bolt, lying below said protrusion of saidlockbolt, is shaped into a bevel at an angle mating with that of saidramp of said push-button so as to provide for the end of saidpush-button a housing when said push-button, if placed in the lockingposition of said key and if the latter is removed, may be depressedinwards against the action of said second spring.

8. A lock according to claim 7, wherein said lock-bolt includes a stopmeans cooperating with said stator to limit movement of said bolt in alocking direction and wherein said lock-bolt is made with said sidenose,said stop means and said protrusion in one integral piece.

9. A lock according to claim 7, wherein at the end of its stroke saidpush-button is stopped by the maximum compression of said helicalspring.

10. A lock according to claim 7, wherein at the end of its stroke saidpush-button is stopped by the endwise engagement of said ramp with anend wall of said stator.

1. A key-responsive safety lock with a movable lock-bolt biased by aspring to be mounted on a closure construction consisting of a movableclosure panel and a stationary frame, said lock comprising a push-buttonhaving a ramp operating the retraction of said bolt against the actionof said spring, said push-button forming a barrel-like cylindrical plugof the safety lock housed in a stator and accomodating tumbler means,said push-button being movable in rotation and translatory motionthrough direct contact with said stator, said stator being formed with apair of grooves for receiving said tumbler means, said stator beingdirectly secured to one of the two elements consisting of said closurepanel and said stationary frame, said push-button being movable inrotation between two angular rotary positions wherein said tumblerplates and said grooves being aligned with one another, said lock-boltcomprising a protrusion engageable with said ramp so that said springurging said lock-bolt back into its operative outward extending lockingposition serves at the same time the purpose through reaction of saidprotrusion on said ramp of moving said push-button back into its outwardprojecting position when this is allowed by the orientation of saidpushbutton with respect to said grooves of said stator, wherein saidramp of said push-button is formed with a shoulder, whereas said statorhas an intermediate partition wall situated between those statorportions in which said push-button and said lock-bolt are disposed andformeD with a window serving to guide said pushbutton, said shoulder andone edge of said window being in abutting relationship in the one ofsaid rotary positions of said push-button corresponding to the lock-boltlocking position thereof.
 2. A lock according to claim 1 wherein saidprotrusion is situated in the center of said lock-bolt and is providedwith slant edges at an angle matching with that of said ramp of saidpush-button and adapted to cooperate therewith.
 3. A key-responsivesafety lock with a movable lock-bolt biased by a spring to be mounted ona closure construction consisting of a movable closure panel and astationary frame, said lock comprising a push-button having a rampoperating the retraction of said bolt against the action of said spring,said push-button forming a barrel-like cylindrical plug of the safetylock housed in a stator and accommodating tumbler means, saidpush-button being movable in rotation and translatory motion throughdirect contact with said stator, said stator being formed with a pair ofgrooves for receiving said tumbler means, said stator being directlysecured to one of the two elements consisting of said closure panel andsaid stationary frame, said push-button being movable in rotationbetween two angular rotary positions wherein said tumbler plates andsaid grooves being aligned with one another, said lock-bolt comprising aprotrusion engageable with said ramp so that said spring urging saidlock-bolt back into its operative outward extending locking positionserves at the same time the purpose through reaction of said protrusionon said ramp of moving said push-button back into its outward projectingposition when this is allowed by the orientation of said pushbutton withrespect to said grooves of said stator, wherein said lock-bolt comprisesstop means formed by a laterally outwardly protrusion appendix and saidstator comprises means constituted by a window provided in thecorresponding wall of said stator, said appendix and one edge of saidwindow being in abutting relationship when said lock-bolt is in itslocking position.
 4. A lock according to claim 3 wherein said lock-boltwith said protrusion and said stop means is made in one integral piecewith cavities on either side of said protrusion.
 5. A lock according toclaim 4, wherein said spring is positioned below said protrusion withits upper part in said cavity undeneath said protrusion.
 6. A lockaccording to claim 5, wherein there is provided a second helical springcoaxial with said push-button and urging same back into outwardprotruding position, the action of said second helical spring beingthereby added to the reaction of said biasing spring on said lock-bolt.7. A key-responsive safety lock with a movable lock-bolt biased by aspring to be mounted on a closure construction consisting of a movableclosure panel and a stationary frame, said lock comprising a push-buttonhaving a ramp operating the retraction of said bolt against the actionof said spring, said push-button forming a barrel-like cylindrical plugof the safety lock housed in a stator and accommodating tumbler means,said push-button being movable in rotation and translatory motionthrough direct contact with the said stator, said stator being formedwith a pair of grooves for receiving said tumbler means, said statorbeing directly secured to one of the two elements consisting of saidclosure panel and said stationary frame, said push-button being movablein rotation between two angular rotary positions wherein said tumblerplates and said grooves being aligned with one another, said lock-boltcomprising a protrusion engageable with said ramp so that said springurging said lock-bolt back into its operative outward extending lockingposition serves at the same time the purpose through reaction of saidprotrusion of said ramp of moving said push-button back into its outwardprojecting position when this is allowed by the orientation of saidpush-button with respect to said grooves of said stator, a secondhelical spring coaxial with said push-button and urging same back intooutward protruding position being provided, wherein said lock-bolt isformed with a side nose, said lock-bolt biasing spring is offset withrespect to the center line of said lock-bolt and bearing upon said sidenose, a portion of said lock-bolt, lying below said protrusion of saidlock-bolt, is shaped into a bevel at an angle mating with that of saidramp of said push-button so as to provide for the end of saidpush-button a housing when said push-button, if placed in the lockingposition of said key and if the latter is removed, may be depressedinwards against the action of said second spring.
 8. A lock according toclaim 7, wherein said lock-bolt includes a stop means cooperating withsaid stator to limit movement of said bolt in a locking direction andwherein said lock-bolt is made with said sidenose, said stop means andsaid protrusion in one integral piece.
 9. A lock according to claim 7,wherein at the end of its stroke said push-button is stopped by themaximum compression of said helical spring.
 10. A lock according toclaim 7, wherein at the end of its stroke said push-button is stopped bythe endwise engagement of said ramp with an end wall of said stator.